Sometimes the amount of a certain vaccine cannot keep up with the number of people who need it. Vaccine shortages can affect certain areas of the country or the country as a whole. A shortage may last a few days to several months.

In the past, the United States has seen shortages of flu vaccines, pneumococcal conjugate vaccines (PCV), tetanus vaccines (including the DTaP vaccines given to children as a part of their regular immunizations) and others.

What causes vaccine shortages?

A vaccine shortage can occur for many reasons. Some of the factors may be:

The company that makes the vaccine is not able to produce the vaccine fast enough to meet the demand.

The company decides to stop making the vaccine for business reasons.

The vaccine's supplier is not able to send out the vaccine quickly enough.

Often, a combination of these factors causes a vaccine shortage in one or more areas of the country.

What happens during a vaccine shortage?

Your family doctor will receive information about the shortage, how long it will last and what to do until new supplies arrive. Typically, the vaccine supply is not completely wiped out--there are just fewer doses than usual. During this time, doctors give vaccines first to the people who need them most. This list may include the elderly, very young children, pregnant women, people who have certain medical problems and people who plan to travel to other countries. Other people are put on a waiting list and are called in to the doctor's office when the vaccine is available.

How can I get more information?

If you have any questions about vaccine shortages, talk to your family doctor. He or she can give you information about the ways a shortage might affect you, your family and your community.

The Centers for Disease Control and Prevention's National Immunization Program Web site (see "Other Organizations" at the bottom of this handout) contains information about current vaccine shortages in the United States. The website is reviewed and updated weekly.